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• ffmpeg says "No JPEG data found in image" when reading image paths from Linux pipe

  18 septembre 2021, par user16945608

  I'm trying to convert a set of pictures into a video, and I want to read the file paths of the pictures from the pipe. The command I would like to run looks like this :

  


  find dir/*.JPG | sort | ffmpeg -f image2pipe -r 1 -vcodec mjpeg -s 6000x4000 -pix_fmt yuvj422p -i - -vcodec libx264 -s 1080x720 -r 20 -pix_fmt yuv420p out.mkv

  


  But I keep obtaining the No JPEG data found in image error. Here is the full log :

  


  Input #0, image2pipe, from 'pipe:':
  Duration: N/A, bitrate: N/A
  Stream #0:0: Video: mjpeg, yuvj422p(bt470bg/unknown/unknown), 6000x4000, 1 fps, 1 tbr, 1 tbn, 1 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (mjpeg (native) -> h264 (libx264))
[mjpeg @ 0x558e98cd7300] No JPEG data found in image
Error while decoding stream #0:0: Invalid data found when processing input
[swscaler @ 0x558e98ce9440] deprecated pixel format used, make sure you did set range correctly
[libx264 @ 0x558e98cdaac0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
[libx264 @ 0x558e98cdaac0] profile High, level 3.1, 4:2:0, 8-bit
[libx264 @ 0x558e98cdaac0] 264 - core 161 r3039 544c61f - H.264/MPEG-4 AVC codec - Copyleft
2003-2021 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=20 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, matroska, to 'out.mkv':
  Metadata:
    encoder         : Lavf58.76.100
  Stream #0:0: Video: h264 (H264 / 0x34363248), yuv420p, 1080x720, q=2-31, 20 fps, 1k tbn
    Metadata:
      encoder         : Lavc58.134.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: N/A
frame=    0 fps=0.0 q=0.0 Lsize=       1kB time=00:00:00.00 bitrate=N/A speed=   0x
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Conversion failed!


  


  The pictures are in the following format (with mediainfo) and the filenames are in the form DSC_1234.JPG :

  


  Format                                   : JPEG
Video
Format                                   : JPEG
Width                                    : 6 000 pixels
Height                                   : 4 000 pixels
Display aspect ratio                     : 3:2
Color space                              : YUV
Chroma subsampling                       : 4:2:2
Bit depth                                : 8 bits
Compression mode                         : Lossy


  


  Also, I would like to avoid using a solution without piping the paths (with -f image2 -i DSC_%04d.JPG for example). Do you have any idea what's happening ?

  


• ffmpeg-python outputs black screen when trying to save as mp4

  3 mars 2023, par Saya

  This is my code. I am trying to make a video out of all pictures in the pics2 directory using ffmpeg.

  


  import subprocess

command = 'ffmpeg -framerate 1 -i "pics2/Image%02d.png" -r 1 -vcodec libx264 -s 1280x720 -pix_fmt yuv420p Output.mp4'
p = subprocess.call(command, shell=True)


  


  This saves an Output.mp4 successfully but the video has no frames (It is completely black)

  


  How do I solve this ?

  


• Capture a webcam continuously, capturing on-demand to image file

  12 février 2015, par krye

  I am trying to set up a webcam stream that I can take pictures from, using ffmpeg. I’m not sure as to how to set everything up ; I’d like to use RTSP and have a ffmpeg (or ffserver or any combination thereof) instance dumping the webcam stream into a stream, and having another client that would get passively opened that would capture a frame instantaneously with proper synchronization and such.

  The problem I’m encountering is in getting this set up. There seem to be many conflicting responses to this question out there.

  I’d like to read from either /dev/video0 or /dev/video1 (using the video4linux2 format/protocol), and I’d like to capture the frames and store them as PNG images.

  Any help would be greatly appreciated.